1. Field of the Invention
The present invention relates to the editing of printer output data into an output format, and more particularly to a printer that edits line printer output data into a page printer output format and outputs the data.
2. Description of the Related Art
Japanese Patent Laid-Open Publication No. Hei 5-201077 and Japanese Patent Laid-Open Publication No. Hei 10-329369, in which the prior art is disclosed, will be described. The print control method and the print controller disclosed in Japanese Patent Laid-Open Publication No. Hei 5-201077 will be described with reference to FIG. 12. Referring to FIG. 12, a print controller Al, which receives data from a host computer A10, processes received data with a master processor module A100, a slave processor module A110, and a slave processor module A120, one page at a time. The commands transferred between the host computer A10 and the print controller A1 are classified into two types, constraint commands A11A1 and non-constraint commands A11A2, as shown in FIG. 13. Referring to FIG. 14, the constraint command A11A1 is composed of a command A92 which defines parameters effective for all pages of a document, a reset command BA93, a command string A94 composed of drawing attribute parameter setting commands and drawing commands, a reset command BA96, and a page change A95 or a page change A98 which is always added as a page delimiter. Therefore, even if the processors A100, A110, and A120 perform processing in parallel, one page at a time, there is no effect on the print result because there is no format information effective across pages and therefore. However, this print control method and the print controller have the following problems.
The first problem is that, when a non-constraint command A11A2 is executed on a printer controller A11 for printing at a high speed as shown in FIG. 13, the host computer A10 must always convert (A11B) the non-constraint command to a constraint command. In other words, when the type of the host computer A10 changes, conversion A11B from a non-constraint command to a constraint command is necessary.
The second problem is that, when a non-constraint command A11A2 is printed without being converted to a constraint command A11A1, it is judged that the page delimiter is issued only when the specification, such as the paper size or the number of copies which are specified for a page only once, is changed at the start of a page. Therefore, when the character size or the line feeding amount is changed while a page is output and, as a result, the number of lines exceeds the page length, the print result is not output correctly.
Next, the printer disclosed in Japanese Patent Laid-Open Publication No. Hei 10-329369 will be described with reference to FIG. 15. A printer B1 shown in FIG. 15 receives data B21 from a host computer into the receiving buffer via an interface controller B4 of a master board B2. Format information that is searched for is stored in a format information storage unit B6 or B11. Editing units B7 and B12 each reference the received data B21 and the format information storage unit B6 or B11 to start editing. Edited and updated format information and page change information are stored in the format information storage unit B6 or B11. Drawing units B8 and B13 process the edited data B21 and B25 and generate video output data as drawn data B26. A printing unit B9 receives the drawn data B26, manages page numbers, and outputs the video output data to an engine in the DMA output mode. The operation will be described with reference to the timing chart shown in FIG. 16. In FIG. 16, when the master board B2 starts the editing processing of the first page, a slave board B3 starts the pre-editing processing of the first page. Next, when the master board B2 starts drawing processing, the slave board B3 starts editing processing. After the editing processing is completed, changed information is written back into the format information storage unit B6 or B11 and the editing processing of the next page starts by referring to that information. Thus, the print result is always valid even for data whose page change code is not definite. However, a processor must wait during editing processing until the editing processing of the preceding page is completed. Therefore, at the time the pre-editing processing is completed, only the editing of the preceding page is completed. The detection of format information and the detection of the page delimiter, performed during the pre-editing processing, become meaningless. The result is that, after pre-editing processing, only the format information set up for the preceding page is copied into the format information storage area. In addition, when data requires much editing time, performance is significantly reduced.
As described above, the problem with the technology disclosed in the former publication is as follows. When a non-constraint command A11A2 is executed on a printer controller A11 for printing at a high speed, the host computer A10 must always convert (A11B) the non-constraint command to a constraint command. In other words, when the type of the host computer A10 changes, conversion A11B from a non-constraint command to a constraint command for a new computer is necessary. In addition, when a non-constraint command is printed without being converted to a constraint command, it is judged that the page delimiter is issued only when the specification, such as the paper size or the number of copies which are specified for a page only once, is changed at the start of a page. Therefore, when the character size or the line feeding amount is changed while a page is output and, as a result, the number of lines exceeds the page length, the print result is not output correctly.
The problem with the technology disclosed in the latter publication is as follows. After the editing processing is completed, changed information is written back into the format information storage unit B6 or B11 and the editing processing of the next page starts by referring to that information. Thus, the print result is always valid even for data whose page change code is not definite. However, a processor must wait during editing processing until the editing processing of the preceding page is completed. Therefore, at the time the pre-editing processing is completed, only the editing of the preceding page is completed. The detection of format information and the detection of the page delimiter, performed during the pre-editing processing, become meaningless. The result is that, after pre-editing processing, only the format information set up for the preceding page is copied into the format information storage area. In addition, when data requires much editing time, performance is significantly reduced.